Compressed natural gas (CNG) pressure regulator

ABSTRACT

A flow regulator for a compressed natural gas (CNG) system is defined by a housing having at least one inlet port, at least one outlet port and at least one interior passage fluidically interconnecting the inlet and outlet ports. A mechanical bypass valve is disposed between the inlet and outlet ports and enabled by a movable biased feature which moves based on inlet pressure and in which the bypass valve is closed only after inlet pressure is greater than a predetermined threshold. The bypass valve is a fail safe wherein gas regulation does not occur until the inlet pressure is sufficient to close the bypass valve. The flow regulator further includes a coolant bowl defined by a serpentine channel formed in a coolant plate as well as a balanced valve as a regulator control feature in conjunction with a weighting or loading mechanism having a diaphragm.

TECHNICAL FIELD

This application generally relates to the field of compressed naturalgas (CNG) systems, and more specifically to a flow regulator for acompressed natural gas system having a mechanical bypass valve thatenables a regulated mode and a bypass mode of operation, as well asadditional attendant features including a coolant bowl and a balancevalve.

BACKGROUND

Pressure or flow regulators are commonly known for purposes of taking ahigh pressure fluid source and reducing the pressure for porting ofsame. In a typical flow regulator, a fluid source inputted under highpressure (e.g., 3600 psi) is ported to a significantly lower pressure(e.g., 70-150 psi). A number of different and varied applicationsutilize compressed natural gas (CNG). These applications include theautomotive industry in which CNG flow regulator systems have beenemployed for motorized vehicles and the like. A number of these systemsrequire complex and elaborate electrical relay systems that can fail,thereby rendering the system inoperative.

As a result, there is a need in the field to provide a pressureregulator or similar device that includes a mechanical bypass valve topermit or otherwise enable pressure controlled operational modes,including a standard regulated mode and a bypass mode, as needed, basedon inlet and outlet pressures but without compromising the operabilityand performance of the regulator.

Additionally, there are ongoing and general needs in the field toimprove the overall functionality and performance of CNG flow regulatorsand more specifically to address issues in various field relatedapplications, including vehicular based systems.

BRIEF DESCRIPTION

Therefore and according to a first aspect, there is provided a flowregulator for a compressed natural gas (CNG) system, the flow regulatorcomprising a housing having at least one inlet port, at least one outletport, and at least one interior passage that fluidically interconnectsthe inlet and outlet ports. A mechanical bypass valve disposed withinthe at least one defined interior chamber enables a bypass mode ofoperation. When the inlet pressure reaches a predetermined threshold,the bypass valve is closed and the regulator works in its typical (i.e.,regulated) mode of operation. When the inlet pressure is below thepredetermined threshold, the bypass valve remains opened and the flowregulator operates in a bypass mode of operation in order to port thecompressed gas directly to the outlet port.

According to at least one version, the bypass valve includes a movablesensing piston biased by a control spring. When the inlet pressureexceeds the predetermined threshold, the sensing piston is movedsufficiently to overcome the bias of the control spring and move to aposition that closes the valve. When the valve is closed, the regulatoris placed in the regulated mode of operation. While the valve is opened,the regulator is in a bypass mode of operation. As such, the bypassvalve acts as a failsafe, requiring sufficient supply pressure to enableregulated mode operation.

In at least one version, the regulator can include at least one featurethat permits adjustment of the control spring. Preferably, the at leastone adjustment feature is user accessible. A valve plug is acted upon inone version by the movable piston. The valve plug is biased by acompression spring to facilitate opening of the valve when the inletpressure threshold has been achieved. A filter can be optionally addedto compressed natural gas which is routed to the outlet port in thebypass mode.

According to another aspect, there is provided a method for controllingthe flow of compressed natural gas in a flow regulator. The methodcomprises the steps of connecting a mechanical bypass valve between theinlet and outlet posts of the regulator, the bypass valve having asensing feature that is biasedly movable based on the inlet pressure.According to one version, a sensing piston is fluidically coupled to theinlet port of the regulator, the sensing piston being movable relativeto a control spring such that when the inlet pressure reaches apredetermined threshold, the biasing force of the control spring isovercome. When the threshold is achieved, the bypass valve is closedthereby enabling the flow regulator to act in a regulated mode ofoperation. When the inlet pressure is below the predetermined threshold,the flow regulator is maintained in a bypass mode in which gas isdirectly routed from the inlet port to the outlet port withoutregulation. Preferably, the bypass valve is initially maintained in theopen position to act as a failsafe.

According to at least one version, the pressure regulator can include aset of fins that are provided in a pattern that better effects coolingof the compressed natural gas moving during porting thereof. The patternaccording to at least one embodiment is defined by a serpentine loop orcircuit formed in a coolant plate that is fluidically connected betweena set of coolant ports and defining a coolant bowl. Coolant fluid ispassed continually through the defined serpentine circuit to effectconvective heat transfer upon the regulated natural gas.

According to yet another aspect, the herein described flow regulator caninclude a balance valve that is configured to work with the weightingmechanism of the pressure regulator in order to adequately balancevariations in supply pressure.

According to yet another version, there is provided a bypass valve for apressure regulator, the pressure regulator having a housing including aninlet port, an outlet port and at least one interior passageinterconnecting the inlet port and outlet port and in which the bypassvalve is disposed between the inlet port and outlet port. According toone version, the bypass valve comprises a movable sensing piston that isbiasedly connected to a control spring in which a predetermined inletpressure is required to overcome the biasing force of the sensing pistonto enable the valve to close and permit the regulator to assume aregulator mode of operation and in which the regulator otherwise isenabled in a bypass mode of operation in which CNG is ported directlyfrom the inlet port to the outlet port.

The bypass valve can include, according to at least one version, atleast one user accessible feature for selectively adjusting the tensionof the control spring. The valve can also be defined by a valve plug orbody connected to the sensing piston. In at least one version, the valveplug is biased by a compression spring. When the inlet pressure reachesthe predetermined threshold, the valve plug is movable to close thevalve as aided by the compression spring.

One advantage provided is that the design of the herein described bypassvalve enables its overall use as an independent fluid control element.To that end, the bypass valve can be alternatively embodied, forexample, within a manifold with a flow regulator or other suitableapplications and uses.

Another advantage realized by the herein described flow regulator isthat the bypass valve does not require electrical power for purposes ofoperation. That is, the bypass mode of operation is purely mechanical innature and is not subject to electrical failures.

The herein described bypass valve is entirely self-contained and doesnot require external power for purposes of its operation. Furthermore,the bypass valve is preferably configured with a self-closing fail-safemode if fatigue, corrosion or other effects were to accelerate springfailure of the bypass assembly. Still further, the valve is notsufficiently complex and is cheaper in terms of costs than expensiveelectrical relay systems.

Yet another advantage realized by the present invention is that thefinned coolant bowl creates a tortuous coolant path which is disposedabout a central location. Functionally, the design of this coolant bowleffectively removes the potential for heavy hydrocarbons condensing bymeans of thermal expansion.

Yet another advantage realized is the inclusion of a balance valve foruse in a CNG flow regulator to stabilize variations in supply pressure.

These and other features and advantages will be readily apparent fromthe following Detailed Description, which should be read in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side perspective view of a flow regulator in accordance withan embodiment;

FIG. 2 is an exploded top perspective view of the flow regulator of FIG.1;

FIG. 3 is a partial view, shown in section, of the interior of thehousing of the flow regulator of FIGS. 1 and 2, showing various definedpassages;

FIG. 4 is a side sectioned view of a portion of the flow regulator ofFIGS. 1-3, depicting a mechanical bypass valve in relation to the inletand outlet ports of the flow regulator;

FIG. 5 is a side sectioned view of the flow regulator of FIGS. 1-4,including coolant connections for the flow regulator;

FIG. 6 is a bottom perspective view of the flow regulator of FIGS. 1-5;and

FIG. 7 is a side sectioned view of the flow regulator of FIGS. 1-6,further depicting a balance valve assembly in cooperation with theadjustable weighting or loading mechanism of the flow regulator; and

FIG. 8 is a side sectioned view of the flow regulator further depictinga pressure relief and release valve.

DETAILED DESCRIPTION

The following relates to a single embodiment of a flow regulator for usein connection with a compressed natural gas (CNG) system, such as thosefound in motorized vehicles. As discussed herein, the flow regulatorincludes a number of resident features, including a mechanical bypassvalve assembly, among others. It will be understood that the specificapplications for the herein described flow regulator can be suitablyvaried. In addition, certain terms are used throughout in order toprovide a suitable frame of reference in regard to the accompanyingdrawings. These terms, which include “inner”, “outer”, “interior”,“exterior”, “above”, “below”, “top” and “bottom”, among others, are notintended to narrow the overall scope of the herein described flowregulator, including the claims, except where so specifically indicated.

For purposes of this discussion, the terms “distal” and “proximal” referto the side or end closest to the interior of the regulator and the sideor end closest to the user, respectively.

As used herein, the terms “a”, “one”, and “the” as used herein areintended to refer to a single quantity of a feature or item. However,these terms can also refer to the presence of “at least one” (i.e., aplurality) of a feature or item.

Referring to FIG. 1, there is shown a flow regulator 100 made inaccordance with the herein described embodiment. The flow regulator 100is defined by a housing 104 made from a suitable structural material.The regulator housing 104 is defined by a top surface, a plurality ofside or lateral walls, and a bottom surface including a bottom extendingportion. More specifically and according to this embodiment, theregulator housing 104 is defined by a substantially rectangularconfiguration with regard to the lateral walls with the exception of anangled surface between two of the side walls at one corner thereof. Itwill be readily apparent from the following discussion that this designprovides a number of packaging advantages. However, the specific designof the regulator housing 104 (shape, geometry) can be suitably varied.

The housing 104 supports a plurality of connections/ports, including aninlet port 108 and at least one outlet port 112, each of the ports 108,112 extending into the interior of the flow regulator 100. In additionand according to this embodiment, a pair of cooling ports 118, 122 arefurther provided adjacent the inlet port 108 along one side wall of thehousing 104. As further discussed herein, the cooling ports 118, 122 arecommonly connected to a source of fluid (not shown) by means of acooling circuit disposed in the regulator 100.

According to this specific embodiment, the inlet port 108 is disposed onthe same side wall as the cooling ports 118, 122, the latter of whichare disposed in a parallel and stacked configuration. The outlet port112 is disposed on the angled side wall with an adjacent port 114 beingprovided for an outlet pressure sensor.

A solenoid valve 116 is mounted onto an adjacent side of the housing104, as well as an inlet pressure sensor 117, FIG. 4, that isfluidically connected to the inlet port 108. Additionally, a pressurerelease and relief valve (partially shown) is also disposed between thecoolant ports 118, 122 and the inlet port 108. It will be readilyapparent that the location of the specific ports and valves can bevaried, provided the necessary functions can be carried out.

An adjustable weighting or loading mechanism is attached to the topsurface of the regulator housing 104 including a bonnet 140, while acontrol element or feature (e.g., a balance valve) is disposed withinthe extending bottom portion of the housing 104. The housing 104 furtherretains a bypass valve 224. Each of these resident features will befurther discussed in greater detail in a later portion of thisdescription.

For purposes of use, the inlet port 108 is configured by means of a barbor other connection feature (not shown) to receive compressed naturalgas (CNG) from an external source (not shown) through a hose, a pipe orthe like. The outlet port 112 of the herein flow regulator 100 issimilarly configured, for example, for connection to an engine (notshown) of a motorized vehicle (not shown). In addition, a set ofmounting holes 126 are further provided to enable attachment of the flowregulator 100 to the engine.

An exploded view of the flow regulator 100 is shown in FIG. 2. Withreference to FIGS. 2 and 7, and mounted to the top (as shown, accordingto the accompanying drawings) of the regulator housing 104 is theweighting or loading mechanism that includes the bonnet 140 mounted bymeans of a plurality of bonnet fasteners 144, such as bolts, screws orother suitable mounting components. The bonnet 140 is defined by anupper hollow cylindrical portion 143 and a lower circular plate 148having a plurality of peripheral fastening holes 152 to enable thebonnet 140 to be secured to the top surface of the regulator housing104. The top surface of the regulator housing 104 includes a set ofaligned holes 156 relative to the fastening holes 152 of the bonnet 140to permit securement.

The weighting or loading mechanism of the herein described regulator 100is further defined by a diaphragm 160 having a diaphragm plate 164disposed on a top surface of the diaphragm 160. The diaphragm 160 ismade from a material that permits deflection. For example, elastomericand metallic materials. One end of a load spring 166 is disposed incontact with the diaphragm plate 160 with the remaining end of the loadspring 166 engaged with a spring button 158, each of the foregoing beinghoused within the hollow cylindrical portion 143 of the bonnet 140 whenassembled. A set screw 145 is accessed from the top of the cylindricalportion 143 of the bonnet 140 through a threaded opening, including anexpansion plug 146 at the distal end of the set screw 145 to enableadjustment of the tension of the load spring 166, as needed. A porousplug 147 is further disposed within an opening formed in the cylindricalportion 143 of the bonnet 14.

The diaphragm 160 is further disposed and supported by a diaphragminsert 168 that is seated along with the diaphragm 160 within a top orupper recessed portion 172 formed in the top surface of the regulatorhousing 104 along with a diaphragm seat nut 163, a plug guide 176, apair of sealing elements 177, 178, and a washer 179, each disposedrelative to an center opening formed in the upper recessed portion 172.

According to this embodiment and still referring to FIGS. 2 and 7, abalance valve 180 is further disposed within the regulator housing 104and directly beneath the top recessed portion 172. According to thisembodiment, the balance valve 180 includes a cap 184 retaining the valve180 within the bottom extending portion of the regulator housing 104.The cap 184 includes a sealing member 185, such as an elastomericO-ring, that is disposed between an external surface of the cap 184 anda through opening formed in the bottom extending portion of theregulator housing 104. The lower proximal portion of a valve plug 190 isretained within a distal end cavity of the cap 184, the valve plug 190including an elongate distal portion 191 which extends through a definedpassage formed in the regulator housing 104. The proximal portion of thevalve plug 190 further includes a defined recess sized to accommodate aplug spring 188. One end of the plug spring 188 engages an inner surfaceof the defined recess of the proximal portion of the valve plug 190 andthe remaining end of the plug spring engages an inner surface of thecavity of the cap 184. Sealing members are provided within an annulargroove on the exterior of the proximal portion of the valve plug 190 forengaging the inner wall of the recess of the cap 184. The extendingelongate distal end 191 is partially hollow and upwardly (as depicted)extends through the defined passage of the housing 104 for retentionwithin a recess formed in the lower portion of the diaphragm insert 168.

The diaphragm insert 168 is retained against the bottom surface of thediaphragm 160, the insert 168 including a distal or upper portion thatextends through aligned center openings formed in the diaphragm 160 andthe diaphragm plate 164, the upper portion of the insert 168 beingsecured by the diaphragm seat nut 163.

The diaphragm 160 is retained within an annular groove of the diaphragminsert 168 at the center and the outer peripheral edge of the diaphragm160 is fixedly secured, such that the movement of the valve body 190 issensitive to movement of the diaphragm 160 based on changes to contained(outlet) pressure.

Additionally, the herein described regulator 100 includes a coolingplate 202 that is also disposed in the bottom extending portion of theregulator housing 104. A gasket 206 is disposed onto the top of thecooling plate 202 and relative to a snap ring 214 covering the bottom ofthe regulator housing 104, the snap ring 214 having a center openingthat accommodates the cap 184. A sealing member 210, such as anelastomeric O-ring, is disposed between the cooling plate 202 and thesnap ring 214.

With reference to FIG. 2, a bypass valve 224 is disposed within alignedopenings 225, 226, the latter only shown in FIG. 4, formed in theregulator housing 104, the through openings 225, 226 being formed inopposite walls with a passage 240, FIG. 4, extending through theinterior of the housing 104. The components and functionality of thebypass valve 224 will be discussed in greater detail in a later sectionof this description.

The high pressure solenoid shut-off valve 116 is disposed in relationalong one of the side or lateral walls of the regulator housing 104. Thesolenoid valve 116 is defined as a subassembly that is linkedfluidically to the outlet port 112 and the balance valve 180. Detailsrelating to the functionality and design of the solenoid valve are wellknown and do not form a substantive part of this disclosure.

With reference to FIGS. 2 and 8, the pressure relief and release valve384 includes a valve body 390 having a cavity that accommodates a valvespring 396, with one end of the valve spring 396 engaging an inner wallof the cavity of the valve body 390 and the opposing or distal end ofthe valve body 390 engaging a poppet 400. The poppet 400 includes avalve seat at one (distal) end that engages an opening of a definedcapture pipe 380 having a diameter that is smaller than the valve seat,the capture pipe 380 extending through the interior of the regulatorhousing 104 between the balance valve 180 and the exterior of thehousing 104. The valve body 390 is retained within a widened portion ofthe capture pipe 380, an intermediate portion of which engages ashoulder of the capture pipe 380. The pressure release and relief valve384 is fixedly secured within the capture pipe 380 in which the onlymovable elements are the poppet 400 and valve spring 396. A sealingelement 404 is provided within a defined groove of the poppet 400 forengaging the groove and an inner wall of the valve body 384. Inoperation, excess pressure is released, according to this embodiment, bygas which overcomes the preset tension of the valve spring to unseat thepoppet 400 and allow gas to vent through the porous plug 388, the latterbeing disposed within a proximal opening of the valve body 384 and toatmosphere.

As shown in the sectioned view of FIG. 3, the housing 104 is defined bya plurality of interior channels or passages, a number of which aresized and configured to retain a plurality of components, such as thebypass valve 224, as discussed herein, and a further number of which areconfigured for the passage of fluid (e.g., compressed natural gas). Forexample, the outlet pressure port 114 extends along a defined passage119 that intersects an interior passage 121 extending from the outletport 112.

Among the passages provided in the interior of the regulator housing 104is a passage 240 extending between the through openings 225, 226 onopposite side walls of the regulator housing 104 that retains the bypassvalve 224, FIG. 4. As discussed herein, this latter through passage 240is defined by adjacent axial sections or portions 242, 244, 246, 249,250, (each shown in FIG. 4) each axial section having a differentdiameter. In addition, each of the inlet port 108 and the outlet port112 of the herein described regulator 100 are fluidically connected bydefined passages 124, 121 to the bypass valve 224.

Referring to FIGS. 2-4, the bypass valve 224 is situated between theinlet port 108 and the outlet port 112 within the passage 240 whereinthe inlet port 108 and outlet port 112 are each coupled fluidically tothe bypass valve 224 via the respective channels or passages 124, 121,FIG. 3, formed in the regulator housing 104.

The bypass valve 224, according to this described embodiment, includes asensing piston 228 that is operatively connected to a control spring232. The sensing piston 228, which is fitted and axially movable withina defined axial portion 242 of the through passage 240, includes a pairof spaced grooves defined on an exterior surface of the sensing piston228 that retain a guide ring 248 and a sealing element 252,respectively, for engaging an inner wall of the axial portion 242 of thedefined through passage 240. In one version, the sealing element 252 canbe an elastomeric O-ring.

One end of the control spring 232 is engaged within a recess 264 that isformed in the proximal end of the sensing piston 228. According to thisembodiment, the remaining end of the control spring 232 is supportedwithin a recess 266 that is defined in the distal end of the adjustmentplug 236. The adjustment plug 236 is further defined by a center throughopening 238 that accommodates a user accessible feature, such as a setscrew (not shown) to allow the tension of the control spring 232 to beadjusted. The sensing piston 228 is defined by a piston body or head229, as well as an extending portion 230 that projects axially through anarrowed portion 244, and the adjacent axial portion 246 of the definedthrough passage 240 and into fixed engagement with a valve plug 272, thelatter having a distal cavity sized to accommodate the end of theextending portion 230. The narrowed portion 244 of the defined throughpassage 240 is provided with a sealing element 256, a back-up ring 257and a rod retainer 260 disposed therebetween.

According to this embodiment, the valve plug 272 includes a distal end274 that fixedly receives the axially extending end portion 230 of thesensing piston 228 in the defined cavity. The proximal end 278 of thevalve plug 272 is fitted within a cavity 314 defined in a cap 308 thatcovers the opening 226.

The cap 308 includes an exterior groove 278 that receives a sealingmember 310, such as an elastomeric O-ring, that engages the interior ofthe through passage 400, and more specifically the axial portion 250.

Referring to FIG. 4, the valve plug 272 is axially movable with thesensing piston 228 within the defined through passage 400 and morespecifically within the axial sections 249, 250 and is biased by acompression spring 292. One end of the compression spring 292 isdisposed within the proximal end 276 of the valve plug 272 and morespecifically within a defined cavity formed in the proximal end. Theopposing end of the compression spring 292 is retained within an innerrecess that is formed within the cap 308. The cap 308 is retained withinthe axial portion 250 of the through passage 400, a distal end of thecap 308 engaging a shoulder separating the axial sections 250, 249 ofthe defined through passage 400 and in which the proximal end of the cap308 is accessible through opening 226. An optional filter 312 (shownonly in FIG. 2) is disposed between the interior of the cap 308 and theexterior of the valve plug 272.

As noted, the valve plug 272 is movable within the axial section 250with the axial range of movement being limited by stop surfaces, namelyan inner surface of the cap 308 and a shoulder separating the axialportions 249 and 246 of the defined through passage 400. The inletpassage 124 is fluidically connected with the defined through passage400 of the bypass valve 224 and more specifically axial section 249according to this embodiment. The outlet port 112 is fluidicallyconnected via passage 124 with the adjacent axial section 246 of thedefined through passage 400.

Generally and according to this embodiment, the herein described bypassvalve assembly 224 uses the control spring 232 acting upon the movablesensing piston 228. Accordingly and when the inlet pressure falls belowa calibrated and predetermined level or threshold, the spring loadovercomes the weight of the sensing piston 228 and the valve plug 272 isdisplaced to an open position. As inlet pressure increases based on theflow of entering compressed gas, the piston load overcomes the bias ofthe control spring 232 and allows the sensing piston 228 and the valveplug 272 to move to a closed position. FIG. 4 depicts the bypass valve224 in the closed position in which the passage of CNG is blocked by thepresence of the valve plug 272, which prevents CNG from entering thethrough passage 400. It should be noted that this latter movement isgradual and does not require pressure reference of flow to theatmosphere in order to operate.

According to this embodiment, the control spring 232 can be adjusted orpreloaded by means of the adjustment plug 236. The plug 236 includes anaccessible feature that is preferably exterior of the regulator housing104 to enable the proper spring tension to be placed on the sensingpiston 228 to open the valve plug 272, allow the inlet pressure tobypass the regulator 100, and permit flow of compressed natural gas(CNG) directly to the outlet port 112. This adjustment allows the valveplug 272 with the assistance of the compression spring 292, to closewhen the supply/inlet pressure increases beyond the preset point of thecontrol spring 232. As noted previously, an optional filter 312 for theherein described bypass valve 224 can be provided in the axial section249 in order to filter the compressed natural gas prior to outputtingsame. According to at least one version, the filter 312 would besimilar, if not identical, to the filter disposed when the compressednatural gas is flowing through the interior of the regulator housing 104in the regulated mode of operation.

It should be noted that variations of the herein described bypass valvedesign are possible. For example, the valve plug can be alternativelydefined by a cylindrical end portion extending from the body of thevalve plug for engagement with the movable sensing piston.

With the following description and with reference to the figures, aporting sequence is described in which compressed gas from the fluidsource (not shown) enters the inlet port 108 and is routed through thedefined passage 124 to the bypass valve 224. As noted, the bypass valve224 is initially biased in an open position in which the movable sensingpiston 228 (and guide plug 272) are retained by the control spring 232.As a result, compressed natural gas enters the axial section 249 of thedefined through passage 400 and is routed through adjacent axial section246 and outlet channel 124 to the outlet port 112. As the enteringcompressed gas engages the sensing piston 228, the sensing piston 228(and the guide plug 272) is caused to move axially and against the biasof the control spring 232. In the meantime, the flow regulator 100utilizes the bypass mode of operation as a fail safe with the enteringcompressed gas passing to the outlet port 112 directly through the axialportions 249, 246 of the defined through passage 400 to the outlet port112. In passing, it should be noted that the herein described bypassvalve can be provided as a separate assembly or alternatively used inother applications. For example, the herein described bypass valve couldbe employed in a manifold.

When the inlet pressure is above the predetermined threshold (greaterthan the biasing force of the control spring 232), the bypass valve 224is closed and CNG is no longer permitted to directly enter the throughpassage 400 for routing to the outlet port 112. As a result, theentering compressed gas can only pass into the flow regulator 100against the weighting mechanism, including the spring loaded diaphragm160 and the control feature, e.g., the balance valve 180 according tothis embodiment.

Referring to FIGS. 5 and 6, and according to this described embodiment,the flow regulator 100 can be provided with a defined coolant circuit(also referred to herein as a “coolant bowl”) to reduce the risk ofheavier hydrocarbons and also for purposes of the Joule Thompson effectin order to further stabilize temperature within the housing 104. Forthe sake of clarity, similar parts are herein labeled with the samereference numerals. As previously discussed, a first coolant port 118 isprovided in a lateral or side wall of the regulator housing 104. Morespecifically, the first coolant port 118 includes a barb 324 or othersuitable connector that enables a hose (not shown) to be connectedthereto from a source (not shown) of compressed natural gas (CNG). Asshown most clearly in the sectioned view of FIG. 5, the first coolantport 118 is coupled to an axial passage 328 extending within theinterior of the regulator housing 104. A connected passage 332 extendstransversely (downwardly as shown in FIG. 5) from the interior end ofthe axially extending passage 328 and exits through an aligned opening333, FIG. 6, formed in the lower or bottom surface 203 of the coolantplate 202.

The second coolant port 122 similarly includes a barb 324 or otherconnector linking same to the fluid source (not shown) through a hose orother form of connection. This coolant port 122 also includes an axiallypassage 336 extending through the interior of the regulator housing 104and a transverse (downwardly according to this view) passage 340(partially shown in this view) extending from the interior end of theaxially extending passage 336. The transverse passage 340 terminates,according to this embodiment, through an aligned through opening 344,FIG. 6, provided in the coolant plate 202.

Linking the openings 333 and 344 of the coolant plate 202 and completinga loop or circuit is a defined serpentine track portion that is formedon the lower or bottom surface 203 of the coolant plate 202. Accordingto this embodiment, coolant is input through the first input port 118per arrow 345 and directed back to the coolant source (not shown) viaarrow 346. The serpentine track portion according to this specificembodiment is defined by a recessed channel 348 that is formed bysuitable machining to an appropriate depth into the lower surface 203 ofthe coolant plate 202. The depth of the recessed channel 348 can bevaried over at least a portion of the defined track or can be made to besubstantially constant. According to this embodiment, the recessedchannel 348 is defined about an unmachined center portion 354 of thecoolant plate 202. More specifically and as machined therein, aplurality of spokes 350 radially extend from the center portion 354 inan evenly spaced manner. According to this embodiment, a series of eight(8) spokes 350 are provided at spaced 45 degree increments. The majority(6) of the formed spokes 350 are identical and defined by a member thatprojects radially from the center portion 354 and terminates with acurved end extending a predetermined distance from the outer peripheraledge of the coolant plate 202. This predetermined distance defines thewidth of the recessed channel 348. The recessed channel 348 originatesat the opening 333 and terminates at the opening 344. An unmachinedportion of the coolant plate 202 forms a wall 362 between the openings333 and 344 at one of the 45 degree increments. One side of the formedwall 362 adjacent the opening 333 is curved to essentially correspond tothe shape of the opening 333. The opposite side of the formed wall 362according to this embodiment is essentially planar. The remaining spoke366 is curved in a manner that follows a portion of the outer edge ofthe opening 333. This latter spoke 362 is significantly thicker than theremaining defined spokes 350 wherein the serpentine track portion isdefined by a plurality of circumferentially spaced C-shaped tracksections 370 of substantially constant width formed about each of thespokes 350.

Entering coolant fluid from opening 333 is caused to move around thethickened spoke 366 along the defined passage 348 and about each of thespokes 350 in a back and forth manner in which fluid is caused to moveboth radially and circumferentially along the formed serpentine trackportion. The coolant fluid is then directed from the passage throughopening 344 and the output port via passages 340 and 336, respectively.As noted and according to this embodiment, the first and second coolantports 118, 122 are formed in the same side wall of the regulator housing104 with the first coolant port 118 being disposed directly above thesecond coolant port 122. It will be readily apparent, however, thatother suitable configurations can be utilized.

As a result, coolant fluid (not shown) is directed in a loop or circuitin which fluid is input through the first coolant port 118 and passages328, 332 through the opening 333 in the coolant plate 202. The fluid isthen directed through the defined serpentine track portion along themachined channel 348 formed in the lower or bottom surface 203 of thecoolant plate 202, providing uniform convective heat transfer for theregulator 100. The coolant fluid is then circulated through the opening344 of the coolant plate 202 and passages 340, 336, respectively, to thesecond coolant port 122 and back to the fluid source (not shown).

In operation and while compressed natural gas is being directed throughthe interior of the housing in the regulated mode of operation, thereduction in pressure and volume of the gas produces corresponding risesin temperature. Therefore and to counteract the temperature increase ofthe compressed natural gas, coolant fluid is directed from the source(not shown), into the coupled first coolant port 118 and through theaxial tubular passage to the transversely (downwardly) extending passagethat extends to the serpentine track portion 336 on the coolant plate.Coolant fluid entering the track portion 336 is caused to move in acounterclockwise fashion about an extending curved spoke 341 and then ina serpentine fashion about each of the defined spokes 340 and along thedefined recess/path to the exit opening. Coolant fluid is caused to exitupwardly to the tubular extension and then to the axial tubular passageand then through the second outlet port 122 and a hose (not shown)connected thereto. The serpentine pattern 340 formed creates a coolantbowl that effectively provides convective cooling of the enteringnatural gas under pressure into the herein described regulator 100.

PARTS LIST FOR FIGS. 1-8

-   100 regulator, flow-   104 housing, regulator-   108 inlet port-   112 outlet port-   114 port for outlet pressure sensor-   116 solenoid valve-   117 inlet pressure sensor-   118 coolant port, first-   119 passage-   121 passage-   122 coolant port, second-   124 passage-   126 mounting holes-   140 bonnet-   143 cylindrical portion, upper-   144 bonnet fasteners-   145 set screw-   146 welsh expansion plug-   147 porous plug-   148 plate, lower-   152 fastening holes, peripheral-   156 aligned holes-   158 spring button-   160 diaphragm-   163 diaphragm seat nut-   164 diaphragm plate-   166 load spring-   168 diaphragm, insert-   172 top or upper recessed portion, regulator housing-   176 plug, guide-   177 sealing element-   178 sealing element-   179 washer-   180 valve, balance-   184 cap-   185 sealing member, cap-   188 plug spring-   190 valve, plug-   191 elongate distal portion, valve plug-   192 back-up ring-   194 sealing element-   198 filter, regulator-   202 coolant plate-   203 bottom or lower surface, coolant plate-   206 gasket, coolant plate-   210 sealing member-   214 snap ring-   224 bypass valve-   225 opening-   226 opening-   228 piston, sensing-   229 piston body-   230 extending end, piston-   232 control spring-   236 adjustment plug-   238 through opening, adjustment plug-   240 passage, through-   242 axial portion, passage-   244 axial portion, passage-   246 axial portion, passage-   248 guide ring-   249 axial portion, passage-   250 axial portion, passage-   252 sealing element-   256 sealing member-   257 back up ring-   260 retainer, piston rod-   264 recess, sensing piston-   266 recess, adjustment plug-   272 valve plug-   274 distal end, valve plug-   276 proximal end, valve plug-   280 recess, proximal end of valve plug-   292 compression spring-   308 cap-   310 sealing member, cap-   312 filter-   314 cavity, cap-   324 barb-   328 axial extending passage-   332 transverse extending passage-   333 opening, coolant plate-   336 axial passage-   340 transverse extending passage-   344 opening, coolant plate-   344 center portion-   345 arrow-   346 arrow-   348 recessed channel-   350 spokes, radially extending-   354 center portion-   362 wall-   366 spoke, thickened curved-   370 c-shaped track sections-   380 capture pipe (pressure relief)-   384 pressure release and relief valve-   388 porous plug-   390 housing, valve-   396 valve spring-   400 poppet-   404 sealing member, pressure release and relief valve

It will be readily apparent that numerous modifications and variationscan be made based upon the inventive concepts that are described herein,including the following appended claims of this application.

The invention claimed is:
 1. A flow regulator for a compressed naturalgas (CNG) system, the regulator comprising: a regulator housing havingat least one inlet port, at least one outlet port and an interior havinginterior channels fluidically interconnecting said ports; and amechanical bypass valve disposed within the regulator housing, thebypass valve enabling a bypass mode of operation based upon sensed inletpressure wherein the mechanical bypass valve comprises a control springacting on a movable sensing piston in relation to the inlet port, thebypass valve being biased by the control spring into an open position toinitially permit a bypass mode of operation until a predetermined inletpressure threshold is reached, the sensing piston being operativelycoupled to a valve plug that is biased by a compression spring andconfigured to close the bypass valve when the inlet pressure reaches andexceeds the predetermined threshold.
 2. The flow regulator as recited inclaim 1, in which the control spring applies a biasing force that mustbe overcome by the inlet pressure in order to close the bypass valve. 3.The flow regulator as recited in claim 1, in which the bypass mode isinitially maintained in an open position to promote the bypass mode ofoperation as a fail safe.
 4. The flow regulator as recited in claim 1,further comprising at least one set of fins for controlling temperatureof the contained compressed natural gas.
 5. The flow regulator asrecited in claim 4, in which the set of fins extend as a serpentinecircuit in a coolant plate between an inlet coolant port and an outletcoolant port.
 6. The flow regulator as recited in claim 1, including atleast one accessible feature for selectively adjusting a tension of thecontrol spring.
 7. The flow regulator as recited in claim 1, wherein thebypass valve further includes a filter disposed in relation to a valveseat.
 8. The flow regulator as recited in claim 1, in which a loadingmechanism includes a spring-loaded diaphragm and a control feature forregulating a flow of gas from the inlet port to the outlet port when thebypass valve is closed, said control feature comprising a balance valve.9. A method for controlling the operation of a pressure regulator, saidmethod comprising the steps of: providing a mechanical bypass valvebetween an inlet port and an outlet port of the regulator, the bypassvalve receiving flow from the inlet port acting upon a movable feature;maintaining the valve in an open position until an inlet pressureexceeds a predetermined threshold wherein the bypass valve comprises asensing piston in fluid communication with the inlet port, the sensingpiston being movable relative to a biased control spring that maintainsthe valve in the open position and in which the sensing piston is linkedto a valve plug that is biased by a compression spring, and in which thevalve plug is configured to close the bypass valve when the inletpressure exceeds the predetermined threshold.
 10. The method as recitedin claim 9, including the step of providing an accessible feature forcontrolling a tension of the control spring.
 11. The method as recitedin claim 9, including the step of providing at least one set of fins forcontrolling temperature of flowing compressed natural gas.
 12. Themethod as recited in claim 11, wherein the at least one set of fins aredefined in a serpentine circuit that extends within a coolant plate, thecircuit extending between an inlet coolant port and an outlet coolantport.
 13. A bypass valve for a pressure regulator, the pressureregulator having a housing including an inlet port, an outlet port andat least one interior passage interconnecting the inlet port and outletport and in which the bypass valve is disposed between the inlet portand outlet port and comprises: a sensing piston that is biasedlyconnected to a control spring that maintains the bypass valve in an openposition until a predetermined inlet pressure overcomes the biasingforce of the sensing piston to enable the valve to close and permit theregulator to assume a regulator mode of operation and in which theregulator otherwise is enabled in a bypass mode of operation in whichgas is ported directly from the inlet port to the outlet port; and avalve plug operatively coupled to the sensing piston, the valve plugbeing biased by a compression spring in which the compression springacts upon the valve plug to close the valve when a predetermined inletpressure threshold has been reached.
 14. The bypass valve as recited inclaim 13, including at least one user accessible feature for selectivelyadjusting a tension of the control spring.
 15. The bypass valve asrecited in claim 13, including a filter disposed in relation to a valveseat through which gas passes when the valve is open.
 16. The bypassvalve as recited in claim 13, in which the valve plug includes anaccessible feature to permit adjustment of the valve plug.
 17. Thebypass valve as recited in claim 13, in which the regulator is used toregulate compressed natural gas.
 18. The method as recited in claim 9,in which the pressure regulator is used to regulate a flow of compressednatural gas.
 19. The method as recited in claim 9, in which a flow ofcompressed natural gas from the inlet port to the outlet port isregulated in a regulator mode of operation when the bypass valve isclosed upon the inlet pressure exceeding the predetermined threshold inwhich the regulator comprises a loading mechanism including aspring-loaded diaphragm and a balance valve for regulating the flow ofgas from the inlet port to the outlet port.